package org.reggie.filter;

import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.reggie.common.BaseContext;
import org.reggie.common.R;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

//检查用户是否登录
@WebFilter(filterName="loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();// /backend/index.html

        log.info("拦截到请求：{}",requestURI);

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",//登录不拦截
                "/employee/logout",//退出登录不拦截
                "/backend/**",//backend的静态资源不拦截
                "/front/**",//front的静态资源不拦截
                "/user/sendMsg",//移动端发送短信不拦截
                "/user/login"//移动端登录不拦截
        };

        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        //3、如果不需要处理，则直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1、判断后端登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("employee") != null){
            log.info("用户后端已登录，用户id为：{}",request.getSession().getAttribute("employee"));

            //将用户id放入线程
            long empId = (long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);
            return;
        }

        //4-2、判断移动端登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user") != null){
            log.info("用户移动端已登录，用户id为：{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        //未登录的跳转页面在前端的request.js中实现，将R对象转成JSON后传给这个js文件
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }


      //路径匹配，检查本次请求是否需要放行

    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
